An anti-actin monoclonal antibody inhibits the zona pellucida-induced acrosome reaction and hyperactivated motility of human sperm.

We report an inhibitory effect of an anti-actin monoclonal antibody (mAb) on the human zona pellucida (ZP)-induced acrosome reaction (AR). Motile sperm were incubated with native human ZP for 2 h in medium containing either the anti-actin mAb, an irrelevant control mAb or cytochalasins B or D (40 micromol/l). Sperm bound to the ZP were recovered and the AR was determined by fluorescein-labelled Pisum Sativum agglutinin. Anti-mouse immunoglobulin G (mIgG) Dynabeads, immunofluorescence and immunogold were used to detect the location of the anti-actin mAb in sperm. The anti-actin mAb significantly inhibited the ZP-induced AR (equivalent to cytochalasins), the ionophore A23187-induced AR and hyperactivation of sperm in medium. After incubation with anti-actin mAb, anti-mIgG beads bound to the head of >50% of sperm recovered after binding to the ZP and 10% of sperm remaining in the medium. The proportion of sperm that bound anti-mIgG beads after recovery from binding to the ZP in the presence of the anti-actin mAb was significantly correlated with the ZP-induced AR in the absence of the antibody. Immunofluorescence and immunogold demonstrated entry of the anti-actin mAb into sperm. This study suggests that the sperm plasma membrane becomes permeable to the anti-actin mAb during capacitation and initiation of the AR.     

Disseminated talc granulomatosis. An unusual finding in a patient with acquired immunodeficiency syndrome and fatal cytomegalovirus infection

The association of disseminated magnesium silicate talc granulomatosis and acquired immunodeficiency syndrome is reported in a male homosexual who used intravenous drugs and who died of overwhelming cytomegalovirus (CMV) infection. Autopsy findings included widespread deposition of talc crystals in the lungs, liver, lymph nodes, bone marrow, and spleen. Typical CMV inclusions were seen in the lungs, kidneys, adrenal glands, gastrointestinal tract, and right eye. There was no evidence of malignancy. Analysis of peripheral blood neutrophil function revealed impaired chemotaxis and chemokinesis, but opsonophagocytosis had remained normal. The CMV infection in the small bowel was extensive and resulted in severe destruction of the muscularis propria and neural plexi, leading to marked dilatation and persistent diarrhea. The terminal course was marked by intractable hypotension, pneumonitis, and malnutrition, which could be attributed respectively to CMV involvement of the adrenal glands, lungs, and small bowel. The etiology and possible role of systemic talc granulomatosis in the development of immunosuppressive illness is reported herein.     

Reliability of the acetabular teardrop as a landmark

Summary This study investigated the effect of tilt and observer reliability on radiographic measurements of the position of a prosthetic acetabular cup in seven dry bone pelves using the teardrop as a landmark. Coronal or sagittal tilt of more than five degrees was easily recognisable and there was effectively no observer variation in the measurements up to this limit. In addition, 90 out of 100 randomly selected antero-posterior pelvic radiographs from an outpatient department were not significantly rotated and 93 demonstrated a clearly defined teardrop. Measurements about the teardrop on routine radiographs are therefore sufficiently accurate to allow assessment of prosthetic position.

---

La valeur du sourcil cotyloidien comme repère d'analyse radiologique

Résumé Cette étude, conduite sur 7 bassins secs, apprécie l'effet de l'inclinaison du bassin sur la qualité de l'analyse radiographique de la position d'une cupule prothétique de hanche en utilisant le sourcil cotyloïdien comme repère. Une inclinaison du bassin dans les plans coronal et sagittal est aisément détectable et il n'existe pas de variation d'analyse entre les différents observateurs en dessous de 5° d'inclinaison. De plus, sur 100 radiographies antéro-postérieures de bassin choisies au hasard dans les dossiers de consultation, 90 avaient été réalisées sans incidence particulièrement adaptée et l'on pouvait repérer facilement le sourcil sur 93% d'entre elles. Les mesures faites sur des radios de routine sont donc suffisamment précises pour permettre l'évaluation de la position d'une prothèse à partir du sourcil cotyloïdien.

     

Selective vulnerability of unmyelinated fiber Schwann cells in nerves exposed to local anesthetics

When peripheral nerves of experimental rats are exposed to local anesthetics, distinctive and reproducible pathologic changes occur involving the perineurial sheath and endoneurial contents. Application of intermediate strength concentrations of the local anesthetics, 2-chloroprocaine, lidocaine, etidocaine, and intermediate or high concentrations of procaine to the surface of rat sciatic nerves resulted in the following changes. By 48 hours, the perineurial sheath exposed to the drug was disrupted and became permeable to granulocytes which infiltrated the subjacent endoneurium in conjunction with edema formation in the endoneurial interstitium. Application of 10% procaine to exposed nerve resulted in extensive demyelination. The most striking pathologic change occurring with either intermediate or high doses was accumulation of lipid droplets in Schwann cells, a phenomenon that occurred often in myelin-producing Schwann cells but much less frequently in unmyelinated fiber Schwann Cells. Lipid accumulation appears to be one of several reactive changes that affect Schwann cells of myelinated fibers and is dose-dependent. On the other hand, while reactive changes were infrequently seen in unmyelinated fiber Schwann cells, these cells appeared more susceptible to injury as shown by electron microscopy. Injury to Schwann cells by local anesthetics is temporary because these cells can replicate quickly. Autoradiographic studies of thymidine incorporation 1 week after procaine administration to the sciatic nerve showed intense proliferation of Schwann cells, but no such activity in controls. These findings support the view that their neurotoxic properties may account in some part for the function of local anesthetics, that Schwann cells of small unmyelinated fibers are more vulnerable to these agents than those of myelinated fibers, and that destruction of their supporting cells is followed by vigorous mitotic activity in the endoneurium.     

Identification of very early lymphoid precursors in bone marrow and their regulation by estrogen

Estrogen is a negative regulator of lymphopoiesis and provides an experimental tool for probing relationships between lymphocyte precursors and stem cells. We found that expression of lymphocyte-associated genes and immunoglobulin (Ig) gene rearrangement occurred before CD45R acquisition. Lymphoid-restricted progenitors that were Lin(-)IL-7R alpha(+)c-kit(lo)TdT(+) (lineage marker(-), interleukin receptor 7 alpha(+), c-kit(lo) and terminal deoxynucleotidyl transferase(+)) were selectively depleted in estrogen-treated mice; within a less differentiated Lin-c-kit(hi) fraction, functional precursors of B and T, but not myeloid, cells were also selectively depleted. TdT and an Ig heavy chain transgene were detected within a hormone-regulated Lin(-)c-kit(hi)Sca-1(+)CD27(+)Flk-2(+)IL-7R alpha(-) subset of this multipotential progenitor population. Identification of these extremely early lymphoid precursors should facilitate investigation of the molecular mechanisms that control lineage-fate decisions in hematopoiesis.     

Transitions to parenthood: his,hers, and theirs

This study explores marital processes that may underlie the apparent decline in satisfaction with marriage in partners becoming parents for the 1st time. The study assessed 47 couples expecting a 1st child and 15 couples not yet decided about having a child at pretest, post 1 (6 months post partum of 9 months after pretest) and post 2 (18 months postpartum or 21 months after pretest). Questionnaires examined: 1) psychological sense of self; 2) partners' role arrangements and communication; 3) parenting ideology; 4) perceptions of the family of origin; and 5) social support and life stress, including parents' work patterns. Parenthood seems to bring more change, and more negative change, in each of the 5 domains of family life that were investigated for comparable couples not having a 1st child experience over a similar period of time. Quantitative data support this conclusion in 4 of the 5 domains (individuals sense of self, marital, parent-child, and outside the family). Interview data suggest that new parents' relationships with their families of origin also undergo change at this time. Although shifts within domains often showed patterns similar to change in overall satisfaction with the marriage, the connection between the 2 was not linear and direct, especially for women. Men and women in transition to parenthood become increasingly different from one another; the results suggest that increased gender differentiation accompanying the transition to parenthood is a factor in accounting for marital satisfaction decline.     

Changing Levels of Social Engagement with Gay Men Is Associated with HIV Related Outcomes and Behaviors: Trends in Australian Behavioral Surveillance 1998–2020

Archives of Sexual Behavior - Changes to how gay, bisexual, and other men who have sex with men (GBM) connect with each other and with their communities have implications for HIV prevention. Social...     

Decreased accumulation of endogenous brain-derived neurotrophic factor against constricting sciatic nerve ligatures in streptozotocin-diabetic and galactose-fed rats

Anterograde and retrograde trafficking of brain-derived neurotrophic factor (BDNF) was examined in streptozotocin-diabetic and galactose-fed rats by measuring accumulation of endogenous neurotrophin proximal and distal to two constricting sciatic nerve ligatures and by direct injection of radiolabeled neurotrophin into the sciatic nerve. Compared to controls, accumulation of endogenous BDNF proximal and distal to the ligatures as well as basal levels in non-ligated nerve segments were decreased in streptozotocin-diabetic and galactose-fed rats. Neither streptozotocin diabetes nor galactose intoxication affected the amount of 125I-labeled BDNF retrogradely transported to the DRG after injection into the sciatic nerve. These results suggest that reduced anterograde and retrograde accumulations of BDNF in experimental diabetes are not a result of impaired capacity for receptor-mediated transport.     

Osteosarcomatosis

A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.